1. Field of the Invention
This invention relates to suspension systems for vehicles. In one of its aspects, the invention relates to a resilient reaction bar which dampens low amplitude and high frequency vibrations in suspension systems.
2. State of the Prior Art
Air spring suspensions are currently used to suspend the front steering axle of buses or other vehicles. Typically the air spring is mounted between the frame and a trailing arm which in turn is pivotably mounted to the frame through a frame bracket. The axle is mounted beneath the air spring and deflection of the assembly (or suspension unit) is limited by the trailing arm. Due to inherent looseness caused by wear in the steering linkage, joints and mechanisms, shimmying of the front wheels often results when the vehicle traverses a bump in the road such as a joint or tar strip. This shimmying loosens up bolts and tends to make the problem worse.
In order to overcome this problem, a rigid track bar was connected between the frame on one side of the vehicle and the lower end of the trailing arm in a suspension on the other side of the vehicle. However, the track bar did not damp the low amplitude, high frequency vibrations because of the design problems and looseness in the steering system.
Similar types of low amplitude, high frequency vibrations occur in other types of suspension systems, including leaf springs and torque arm bogie suspension systems.